Many people who have aladdin kerosene heaters really love them. There are not many things that can go wrong with a simple unit like this, so they can last for years. Many are older than their owners!
Though you now need to track down an aladdin in the antique stores or via ebay, these remain reliable and surprisingly energy efficient space heaters.
This is because they are so straightforward a tank of kerosene (use good quality) and a wick. Not much more to it. This means if you do pick up a classic like the aladdin blue flame then it is often possible to use it as a working indoor kerosene heaters.
If you get one in good external order that is working you should do a couple of things. Throw out any kerosene that is in the tank and clean out the tank before refilling with top grade kerosene. Unless the wick looks great, replace it with a new one. These are still available from certain places (an easy Internet search), though some of the new wicks are apparently of lower quality than the originals.
When you use is as one of your portable kerosene heaters do not do so in a tightly sealed room - the space should be reasonably sized and allow some air flow (most houses fit the bill!). Use a carbon monoxide monitor or alarm.
These are great heaters, but if you are not sure, consult an expert. In any case remember that they do not have the auto shutoff safety of a modern unit so keep kids and pets out of the way. A smoke alarm is a good idea in any house, but certainly if you use antique kerosene units!